From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/arch/arm/mach-ep93xx/crunch.c | 88 ++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 kernel/arch/arm/mach-ep93xx/crunch.c (limited to 'kernel/arch/arm/mach-ep93xx/crunch.c') diff --git a/kernel/arch/arm/mach-ep93xx/crunch.c b/kernel/arch/arm/mach-ep93xx/crunch.c new file mode 100644 index 000000000..a4a2ab964 --- /dev/null +++ b/kernel/arch/arm/mach-ep93xx/crunch.c @@ -0,0 +1,88 @@ +/* + * arch/arm/kernel/crunch.c + * Cirrus MaverickCrunch context switching and handling + * + * Copyright (C) 2006 Lennert Buytenhek + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "soc.h" + +struct crunch_state *crunch_owner; + +void crunch_task_release(struct thread_info *thread) +{ + local_irq_disable(); + if (crunch_owner == &thread->crunchstate) + crunch_owner = NULL; + local_irq_enable(); +} + +static int crunch_enabled(u32 devcfg) +{ + return !!(devcfg & EP93XX_SYSCON_DEVCFG_CPENA); +} + +static int crunch_do(struct notifier_block *self, unsigned long cmd, void *t) +{ + struct thread_info *thread = (struct thread_info *)t; + struct crunch_state *crunch_state; + u32 devcfg; + + crunch_state = &thread->crunchstate; + + switch (cmd) { + case THREAD_NOTIFY_FLUSH: + memset(crunch_state, 0, sizeof(*crunch_state)); + + /* + * FALLTHROUGH: Ensure we don't try to overwrite our newly + * initialised state information on the first fault. + */ + + case THREAD_NOTIFY_EXIT: + crunch_task_release(thread); + break; + + case THREAD_NOTIFY_SWITCH: + devcfg = __raw_readl(EP93XX_SYSCON_DEVCFG); + if (crunch_enabled(devcfg) || crunch_owner == crunch_state) { + /* + * We don't use ep93xx_syscon_swlocked_write() here + * because we are on the context switch path and + * preemption is already disabled. + */ + devcfg ^= EP93XX_SYSCON_DEVCFG_CPENA; + __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK); + __raw_writel(devcfg, EP93XX_SYSCON_DEVCFG); + } + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block crunch_notifier_block = { + .notifier_call = crunch_do, +}; + +int __init crunch_init(void) +{ + thread_register_notifier(&crunch_notifier_block); + elf_hwcap |= HWCAP_CRUNCH; + + return 0; +} -- cgit 1.2.3-korg